TY - CONF A1 - Radtke, Martin A1 - Kulow, A. A1 - Reinholz, Uwe A1 - de Oliveira Guilherme Buzanich, Ana A1 - Emmerling, Franziska A1 - Streli, C. A1 - Fittschen, U. E. A. A1 - Hampel, S. T1 - Energy Resolved Imaging with Coded Apertures N2 - Our aim is to develop a simple and inexpensive method for full field X-ray fluorescence imaging.We combine an energydispersive array detector with a coded aperture to obtain high resolut ion images. To obtain the information from the recorded image a reconstruction step is necessary. The reconstruction methods we have developed, were tested on simulated data and then applied to experimental data. The first tests were carried out at the BAMline @BESSY II. This method enables the simultaneous detection of multiple elements,which is important e.g. in the field of catalysis. T2 - SRI 2021 CY - Online meeting DA - 28.3.2022 KW - Synchrotron KW - BAMline KW - Machine Learning KW - Coded Aperture PY - 2022 AN - OPUS4-56298 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beck, Uwe A1 - Hielscher-Hofinger, S. A1 - Rietz, U. A1 - Stockmann, Jörg M. T1 - Materials testing using centrifuge technology a journey through time from 2004 to 2024 N2 - This presentation provides an overview of materials testing using centrifuge technology in the period from 2004 to 2024. The development, the proof of concept, the functional principle, various operating modes as well as applications and examples are shown. T2 - ICDAMT 2024 CY - Berlin, Germany DA - 10.06.2024 KW - Centrifuge technology KW - Materials testing KW - Centrifugal adhesion testing KW - Tensile and cmpressive stress testing PY - 2024 AN - OPUS4-60541 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg A1 - Chemello, Giovanni A1 - Reed, B.P. A1 - Marchesini, S. A1 - Pollard, A.J. A1 - Clifford, C.A. T1 - Reliable measurements of the chemical composition of graphene-related 2D materials with X-ray photoelectron spectroscopy N2 - Graphene and related 2D materials (GR2Ms) are now entering an exciting phase of commercialization and use in products. Graphene nanoplatelets (GNPs) can be obtained in rather large quantities, but the properties of these industrially produced powders can vary depending on the production method, and even from batch to batch. Understanding and optimizing the surface chemistry of GNPs, modified through chemical functionalization processes is crucial, because it affects their dispersibility in solvents and matrices for the purpose of embedding them into real-world products. Therefore, reliable and repeatable measurements of the surface chemistry of functionalized GNPs are an important issue for suppliers as well as users of these materials. To address these concerns, international documentary ISO standards for measurement methodologies are under development which incorporate protocols that are becoming widely accepted in the community. Recently, it was shown that pelletizing led to lower average O/C atomic ratios than those measured for powders [1]. In another study, the influence of the morphology on the degree of functionalization was shown [2]. As expected, a higher degree of functionalization was detected for smaller GNPs. The functionalization was located at the outermost surfaces of the GNPs by comparing experiments using photoelectron with soft (Al Kα, 1.486 keV) and hard X-rays (Cr Kα, 5.405 keV). Therefore, it is important for those using GNPs to understand both the physical and chemical properties of these particles, when considering their use in different applications. The next step for reliable characterization protocols was the realization of an interlaboratory comparison under the auspices of VAMAS (Versailles Project on Advanced Materials and Standards) with 22 participating laboratories from all over the world. Samples of oxygen-, nitrogen-, and fluorine- functionalized GNPs were provided to the participants along with a measurement protocol. Participants were asked to prepare the samples as powders on a tape, powders in a sample holder recess, or as pellets. The lower measured O/C ratio reported for pelletized samples [1] was confirmed. The lowest scattering of the results was observed for the powders measured in the recess (Fig. 1). Furthermore, an influence of the humidity on the results was observed. T2 - ECASIA 2024 CY - Gothenburg, Sweden DA - 09.06.2024 KW - Interlaboratory Comparison KW - Functionalized graphene KW - Sample preparation PY - 2024 AN - OPUS4-60533 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg A1 - Ciornii, Dmitri A1 - Knigge, Xenia A1 - Hodoroaba, Vasile-Dan A1 - Bennet, F. A1 - Meirer, F. A1 - Duijndam, A. A1 - Thünemann, Andreas A1 - Drexel, R. A1 - Fadda, M. A1 - Sacco, A. A1 - Giovannozzi, A.M. A1 - Donskyi, I. A1 - Schusterbauer, R. A1 - Nickl, P. A1 - Reichardt, P. A1 - Altmann, Korinna T1 - Revealing surface functionalities of micro- and nanoplastic particles’ surface by means of XPS N2 - Over the last 20 years, many researchers, politicians, and citizens themselves have become increasingly aware of the growing plastic problem of our time. Inadequate recycling concepts, collection points, and careless dumping of plastic products in the environment lead to an accumulation of plastic. External weather influences can cause these to degrade and fractionate, so that today microplastics (1-1000 µm, ISO/TR 21960:2020) [1] of different polymer materials can be detected in all parts of the world. The precautionary principle applies to microplastics. The particles can break down further to form nanoplastics (<1 µm, ISO/TR 21960:2020) [1]. Whether microplastics or nanoplastics pose a toxicological hazard is being investigated in a variety of ways. Valid results are still pending, however, investigations into the frequency, transport, possible sinks and entry paths must be taken into account. This is why monitoring of microplastics is already required in the revision of the Drinking Water Framework Directive [2]. The same is still pending in the final version of the revision of the Waste Water Framework Directive this year, but is expected. Nanoplastics are particularly under discussion for having a toxic effect on humans and animals, as these particles are small enough to be absorbed by cells. For targeted toxicological studies, it is important to have test and reference materials that resemble the particles found in the environment. To mimic environmental samples, these materials should also have an irregular shape and show aging at the surface, which can be detected with XPS or SEM/EDS. BAM in collaboration with the EMPIR project "PlasticTrace" works on a reference material candidate of nano-sized polypropylene (nano-PP) [3]. The nano-PP vials were tested for homogeneity with PTA and further characterized with bulk and surface-sensitive techniques. An SEM image and a corresponding XPS spectrum are presented in Figure 1. Raman measurements as well as XPS indicate an aged surface. T2 - ECASIA 2024 CY - Gothenburg, Sweden DA - 09.06.2024 KW - Surface chemistry KW - Micro- and nanoplastics KW - X-ray Photoelectron Spectroscopy KW - MNP production technique PY - 2024 AN - OPUS4-60535 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stockmann, Jörg M. A1 - Radnik, Jörg A1 - Hodoroaba, Vasile-Dan A1 - Weimann, T. A1 - Bütefisch, S. T1 - A new XPS test material for more reliable surface analysis of microstructures N2 - Small-area XPS analysis is one of the most popular and powerful methods for analysing the surface of features in the micro-range. When measuring microstructures, the ques-tion arises whether the measuring point is really located at the point intended to be ana-lysed. Information in a measured spectrum might originate within the field of view (FoV) on the surface of the sample, from outside the FoV, or even from inherent contamination. To ensure that small structures can be measured correctly regardless of user and instru-ment, certain instrument and sample settings must be known and selected correctly: beam and aperture size as well as the aperture settings and the approximate dimensions of the structure to be analysed. This is the only way to ensure that the information in the spectrum originates only from the FoV on the analysed structure. To test the performance of the XPS instruments, a dedicated test material was developed that consists of a gold surface on which 8 circles and 8 squares of chrome are incorpo-rated using a masking process, so that the Au substrate and the Cr structure surfaces are in the same surface plane. In order to be able to test as many as possible instruments from different manufacturers, the structures have been designed with a size ranging from 300 µm down to 7 µm. The layout of the test material has been optimised in regard of the handling. The structures are arranged along lines instead of a circumference, marking arrows around the smaller structures (≤50 µm) are added, and the lithography mask is optimised regarding edge and diffraction effects. Furthermore, the manufacturing process was changed from electron-beam deposition to mask lithography due to costs reasons. The structures on the test material were measured with a metrological SEM to determine their accurate dimensions and check the repeatability of the manufacturing process. XPS investigations with a Kratos AXIS Ultra DLD and an ULVAC-Phi Quantes demonstrates the suitability of this new test material for measuring the analysed area. T2 - ECASIA 2024 CY - Gothenburg, Sweden DA - 09.06.2024 KW - Small-area XPS KW - Test material KW - Field of view KW - Imaging PY - 2024 AN - OPUS4-60539 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg A1 - Favre, G. T1 - How to expand the use of your test method? Validation is key towards standardisation N2 - Standardised methods need validation. The main validation parameters like trueness, repeatability and intermediate precision and reproducibility are presented. Furthermore, different methods for the validation are disussed: (certified) reference materials, representative testing materials and interlaboratory comparisons. At last, the need of proficiency testing is stressed. T2 - Materials Week 2024 CY - Limassol, Cyprus DA - 17.06.2024 KW - Validation KW - Reproducibility crisis KW - Metrological traceability KW - Measurement uncertainty PY - 2024 AN - OPUS4-60536 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg A1 - Habibimarkani, Heydar A1 - Abram, Sarah Luise A1 - Prinz, Carsten A1 - Hodoroaba, Vasile-Dan T1 - Comparative chemical analysis of Ni-Fe oxide nanoparticles N2 - Ni-Fe oxide nanoparticles have gained a lot of interest because of their high activity in the oxygen evolution reaction (OER) which is crucial for water splitting. [1] Although there have been great efforts in the last years, the understanding of the synergistic effect between Fe and Ni is still under discussion. Therefore, we prepared different Ni-Fe oxide nanoparticles with different compositions from pure iron oxide to pure nickel oxide adapting a known procedure. [2,3] Size and morphology of the nanoparticles depend on the composition which was shown with Transmission Electron Microscopy (TEM). The compositions of the nanoparticles were measured with a comparative approach using X-ray Photoelectron Spectroscopy (XPS), Hard X-ray Photoelectron Spectroscopy (HAXPES), and Energy Dispersive X-Ray Spectroscopy (EDS) coupled with the TEM providing detailed chemical information of the nanoparticles in different sample regions. EDS reveals that the different sample regions are dominated by one of the components, Fe or Ni, but a slight mixing between the components can be found (see Figure 1), which was confirmed with X-ray Diffraction (XRD). XPS indicates the enrichment of Fe at the sample surface, while HAXPES and EDS data agree on the stoichiometry of the bulk. High-resolution XPS and HAXPES exhibit some differences in the valence states of Fe and Ni, whereas Ni seems to be easier to reduce than Fe. Further investigations combining these different techniques and additionally Secondary Ion Mass Spectrometry (ToF-SIMS) are ongoing by using in situ approaches and coupling cyclic voltammetry to the analytical techniques. T2 - ECASIA 2024 CY - Gothenburg, Sweden DA - 09.06.2024 KW - Oxygen evolution reaction KW - Transmission Electron Microscopy KW - (Hard) X-ray Photoelectron Spectroscopy KW - Synergistic effects PY - 2024 AN - OPUS4-60534 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - Standardisation needs for regulatory testing of graphene and related 2D materials. phy-chem properties N2 - The main properties and main methods which are needed for the physico-chemical characterisation of graphene related 2D materials are discussed. As expample for standardization, protocols for the measurement of the chemical composition with XPS are discussed. The results of an interlaboratory comparisons led to new recommendations for the reliable measurments protocols. T2 - Materials Week 2024 CY - Limassol, Cyprus DA - 17.06.2024 KW - Standardisation KW - Functionalized graphene KW - Interlaboratory comparison KW - Endpoints PY - 2024 AN - OPUS4-60537 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Grotelüschen, Frank A1 - Robert, Eberwein A1 - Berhorst, Ralf T1 - Supertanker für H2: EU-Projekt konstruiert günstigen Riesenspeicher N2 - Wasserstoff stellt einen potenziellen Energieträger für den großskaligen Import von Energie nach Europa dar. Von seinen verschiedenen Speicherformen eignet sich hierfür insbesondere verflüssigter Wasserstoff, mit dem sich auf gleichem Volumen deutlich mehr Energie speichern lässt als bei der druckbasierten Speicherung. Verflüssigter Wasserstoff wird bei minus 253°C gespeichert und muss für dessen Transport lange bei dieser niedrigen Temperatur gehalten werden. Dies stellt besondere Herausforderungen an die thermische Isolation von Tanks. Der Erforschung nachhaltiger, kosten- und energieeffizienter sowie sicherer thermischen Isolationen wird im NICOLHy Projekt, unter Leitung der BAM, nachgegangen. KW - Verflüssigter Wasserstoff KW - Thermische Isolation PY - 2024 UR - https://www.deutschlandfunk.de/supertanker-fuer-h2-eu-projekt-konstruiert-guenstigen-riesenspeicher-dlf-d50ff14a-100.html PB - Deutschlandradio CY - Hamburg AN - OPUS4-60538 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stephan-Scherb, Christiane A1 - Menneken, Martina A1 - Nützmann, Kathrin A1 - Falk, Florian A1 - de Oliveira Guilherme Buzanich, Ana A1 - Witte, Steffen A1 - Radtke, Martin T1 - Early stages of high temperature oxidation/sulfidation studied by synchrotron x-ray diffraction and spectroscopy N2 - Ferritic high temperature alloys are widely used as boiler tube and heat exchanger materials in coal, biomass and co-fired power plants. All technologies have in common that the applied materials are exposed to different temperatures, process pressures and reactive atmospheres that lead to a change of the material properties and a further degradation of the material. Material changes caused by aging in highly corrosive and toxic gases such as SO2 are mainly studied ex situ after the reaction is finished. The solid material is deposited in the atmosphere for a certain period of time, and material changes are then examined by various microscopic techniques such as optical microscopy (OM), electron microprobe analysis (EMPA), scanning electron microscopy (SEM and TEM) and X-ray diffraction (XRD). Nevertheless, extensive efforts were made to study material changes of high temperature alloys under oxidizing and reducing atmospheres by environmental scanning electron microscopy or in situ TEM techniques However, the possibilities of microscopic in situ techniques are very limited for the use of highly corrosive and toxic gases such as SO2. Since Sulfur induced corrosion at temperatures relevant for coal and biomass fired power plants, which is causing breakaway oxidation and sulfide precipitation at grain boundaries, is still of scientific interest, the current work focuses on the effect of SO2 in an initial stage of corrosion of ferritic alloys. For the analysis of early stages of combined oxidation and sulphidation processes of Fe-Cr model alloys the usage of a light furnace to conduct a rapid reactive annealing experiment is feasible. Previous studies presented distinct results of the influence of chromium on early high temperature corrosion by SO2 by this technique and subsequent classical metallographic analyses. However, it is still not possible to trace the corrosion mechanism in real time by conducting single aging experiments. The current work introduces two different approaches to study the initial stages of high temperature oxidation processes by applying above state of the art X-ray diffraction and spectroscopy methods. One part focuses on the real time observation of the formation of corrosion products such as oxides and sulfides by energy dispersive X-ray diffraction (EDXRD). The potential of this technique to study crystallization and growth processes of thin films in a reactive environment in real time was previously shown for different compound semiconductors. This approach was now applied to follow oxidation and sulphidation processes of ferritic model alloys in SO2 and SO2/H2O environments. The diffraction signals of the X-rays were detected during the corrosion process and the peak area and positions were analyzed as a function of time. This procedure enables monitoring external oxide growth and material loss in real time in an early stage of corrosion. The other part of the current work presents the possibilities of X-ray absorption near edge structure spectroscopy (XANES) to characterize oxide scales and their growth mechanisms. Precise phase identification and quantification of corrosion products in a multi-phase oxide/sulfide scale is a pre-requisite to understand diffusion paths of metal ions and gas components. It is a challenging task to distinguish structurally similar reaction products such as Fe3O4 and FeCr2O4 especially in thin films with texture effects by diffraction. To illustrate for example Cr-out diffusion of an alloy throughout an inner and external oxide scale the differentiation of Fe3O4 and FeCr2O4 is indispensable. XANES uses the photoionization effect at the metal absorption edge in an aging product and accesses by this structural and chemical information. The current work uses XANES at the Fe-K and Cr-K absorption edge to identify various aging products grown as thin layers on alloys after short time aging experiments. A reaction chamber for combining high temperature oxidation experiments with surface sensitive X-ray absorption near edge structure spectroscopy will be introduced and first results of XANES on scales at high temperatures will be presented. T2 - ISHOC 2018 CY - Matsue, Japan DA - 22.10.2018 KW - Corrosion KW - Sulfidation KW - In situ KW - Diffraction KW - XANES PY - 2018 AN - OPUS4-47278 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -